A touch screen is an electronic visual display that a user may control through simple or multi-touch gestures by touching the screen with one or more fingers. Some touch screens can also detect objects such as a stylus or ordinary or specially coated gloves. The user can use the touch screen to react to what is displayed and to control how it is displayed, for example, by selecting various objects that are displayed on the screen.
The touch screen enables the user to interact directly with what is displayed, rather than using a mouse, touchpad, or any other intermediate device, other than a stylus, which is optional for most modern touch screens.
Touch screens are common in devices such as game consoles, all-in-one computers, tablet computers, and smart phones. They can also be attached to computers or, as terminals, to networks. They also play a prominent role in the design of digital appliances such as personal digital assistants (PDAs), satellite navigation devices, mobile phones, and video games.
The popularity of smart phones, tablets, and many other types of information appliances is driving the demand and acceptance of common touch screens for portable and functional electronics. Touch screens are popular in the medical field and in heavy industry, as well as in kiosks such as museum displays or room automation, where keyboard and mouse systems do not allow a suitably intuitive, rapid, or accurate interaction by the user with the display's content.
Various technologies have been used for touch screens, including: resistive layers separated by a space, surface acoustic waves, various forms of capacitance coupling, infrared emitters and detectors, optical imaging, acoustic pulse detection, etc.